Locking mechanisms



United States Patent- Inventor William Edward Walker Littlebury Green, Near Saffron Walden, England Appl; No. r 776,179 Filed Nov. 15, 1968 Patented Dec. 29, 1970 Assignee Walker (Enl'ield) Limited Middlesex, England a British Company. a part interest Priority Sept. 12, 1968 Great Britain No. 43464/68 LOCKING MECHANISMS 12 Claims, 5 Drawing Figs.

[1.8. CI 242/72 Int. Cl B65h 75/24 Field of Search 2427/;

[56] References Cited UNITED STATES PATENTS 2,204,475 6/1940 Crandall 242/72X 2.339.543 l/ l 944 Bishop 242/72X FOREIGN PATENTS l 109,4 1 2 4/ l 968 Great Britain 242/72 Primary Examiner-Nathan L. Mintz Altorney Holcombe, Wetherill & Brisebois ABSTRACT: A reel carrier is fonned of a shaft having a number of axially extending, cruciform-section, slots in each of which is disposed a length of chain. Some of the pins of the links of each chain are restrained against radial movement by the lateral rebates of the slots, while others are free to move radially. To lock a reel on the shaft, the chains are put into compression causing the nonretained pins to move out of the slots and into locking engagement with the reel.

LOCKING MECHANISMS This invention relates to a locking mechanism for locking a member to be carried to an elongate carrier and additionally relates to the construction of the elongate carrier itself.

In British specification No. 1,109,412, we have described such a locking mechanism, particularly designed for securing a reel to a reel holder, and comprising a shaft having at least one externally opening, lengthwise extending, slot to receive a length of chain; means were provided for applying to the chain a lengthwise compression force, causing some, but not all, of the pins of the chain to move outwardly of the slot and to engage the reel, thereby locking the reel to the shaftv In the present invention the slot or each slot has a transverse rebate to retain some only of the pins of the links of the chain but leaving free other pins of the chain for radial movement relative to the shaft rebate. In this way, the chain is positively held in the slot, only the said other pins being enabled to move out of the slot to grip the member to be carried by the shaft.

Thus, in accordance with one aspect of the present invention, a reel holder comprises a shaft having at least one externally opening lengthwise-extending slot formed with a transverse rebate; for each slot, a length of chain adapted to be received within the slot with some only of the pins of the links retained by the rebate against radial movementwith respect to the shaft, the remaining pins being free to move radially; and means for applying to the chain a lengthwise compressive force tending to force the nonretained pins out of the slot and into engagement with a member carried by the shaft.

In a preferred form of the invention, a reel holder comprises a shaft having a plurality of externally opening, lengthwise extending, cruciform-section slots, each being formed with a pair of transverse rebates, for each slot at length of chain adapted to be received within the slot and having the pins of some links retained by the rebates against radial movement with respect to the shaft and the-pins of other links free to move radially, and means for applying to each chain a lengthwise compression force tending to force the nonretained pins out of the slots and into engagement with a member carried by the shaft.

The invention will be more readily understood by way of example from the following description of reel holders in accordance therewith, reference being made to the accompanying drawings, in which:

FIG. 1 is an axial section through one end of the reel holder,

FIG. 2 is a section on the line 11-11 of FIG. 1, showing the shaft only, and

FIG. 3 is a similar section on the line III-III of FIG. 1, showing the shaft only,

FIG. 4 is an axial section through one end of an alternative form of reel holder, and

FIG. 5 is a section on the line V-V of FIG. 4, showing the shaft only.

In FIG. 1. only one end of the reel holder is shown, it being understood that the other end is similar to that shown. The reel holder has a cylindrical shaft 12, mounted on stub axles, one of which is shown in FIG. 1 at 13. Three cruciform-section slots 14 are milled into the shaft 12, so as to extend axially from one end to the other and to open to the exterior face of the shaft 12. Thus, each side face of each slot 14 has a recess or rebate 15, the purpose of which .will be explained subsequently. The slots 14 are spaced equally about the circumference of the shaft 12, as shown in FIGS. 2 and 3, and, at each end, the slots are extended, as at 16, to the interior of the shaft. A length of chain 17 is located in each slot 14 and is secured at each end to a block 19 disposed within the slot. A bolt 18 fixed in the block 19 passes through the wall of the shaft and is attached to actuating means to be described hereinafter.

When the chain 17 is at rest it is disposed entirely within its slot 14. Also, the chain is dimensioned so that the heads 20 of the pins of thechain are located in the rebates 15, in which they can slide axially but from which they are unable to move radially. The heads of some selected pins, indicated schematically at 21, are reduced, so that the pins in question are not retained by the rebates 15, but can move out of the slot 14, as shown in FIG. .1.

In use, the blocks 19 are retracted to cause the chains to lie entirely within their slots 14. The reel to be carried is threaded onto the shaft so as to overlie the chain length. Then, the actuating mechanism is operated to apply compressive forces to the chains. Those pins 20 having normal'size heads are held by the rebates 15 against radial movement, but the pins with reduced heads 21 are forced outwardly of the slot 14, engage the interior of the reel and thereby lock the reel to the shaft 12. To make possible the initiation of this radial movement of the pins 21, an outward bias is applied to each. as by a leaf spring, which passes externally of the pins 20 and internally of the pins21; alternatively, each pin 21 may be provided with its own biasing spring.

The arrangement shown in FIGS. 1 to 3 has a pneumatically operated actuating mechanism. For this purpose, each end of the shaft 12 is closed by a cup 22, secured to the end of the shaft by bolts 23 and having an integral pulley 24. The cup 22 carries roller bearings 25 for the stub axle 13, the shaft 12 being mounted on the axles 13 for rotation relative thereto.

Each end of the shaft 12 also has a piston 26, which is biased by a helical compression spring27 towards the respective shaft end and to which the bolts 18 are secured. A nipple valve 28 passes through a passage 29 in the wall of the shaft 12 and communicates with that portion of the cylinder formed by the interior of the shaft 12 between the cup 22 and the piston 26 at the left-hand side of the shaft as viewed in FIG. 1. The corresponding part of the cylinder at the right-hand end of the shaft is in communication with that portion at the left-hand by a flexible pipe 30 which passes through the two pistons by means of two unions, one of which is shown at 31, and through the two springs 27. A further pulley 32 is secured to the exterior of the shaft adjacent the nipple valve 28.

In order to operate the actuating mechanism to lock a reel to the shaft 12, air under pressure is supplied to the nipple valve 28 from an air line. This causes the two pistons 26 to move inwardly towards each other and, by the connections afforded by the bolts 18, to force the two sets of three blocks 19 to move towards each other. When the reel has become securely locked to the shaft, the supply of compressed air is disconnected, the valve 28 preventing the reduction of pressure within the shaft 12. As a result, the reel remains locked, without an air supply, with its attendant disadvantages, being permanently connected to it. When the reel has been extended, the reel core may be released from the shaft 12, simply by operating the valve 28 to release the pressure, when the springs 27 return the pistons 26 and bring the chains 17 again entirely within their slots.

The cruciform-section of the slots 14 ensures that the chains 17 are always retained in the slots by the engagement of the pin heads 20. One advantage stemming from this fact is that the locking mechanism may be employed in conjunction with a reel having an axial length less than the length of the chain; in those circumstances, those pins 21 not enclosed by the reel are first forced out of the slots to their fullest extent, i.e. until the adjacent pins 20 abut one another. Thereafter, the pins 21 enclosed by the reel are urged outwardly against the restraint of the reel and effect the locking action. In this way, a reel holder corresponding to the maximum reel length to be encountered may be employed for holding and locking reels of all lengths.

The reel holder of FIGS. 4 and 5 is generally similar to that of FIGS. 1 to 3, except for the actuating mechanism. Thus, the shaft 12 is provided with the threeslots 14, each of cruciform-section, and each carrying a length of chain, which is similar to the chain 17 and which is retained in the slot in the same manner as shown in FIG. 1. As before, each end of each chain is attached to a block 19, of rather larger dimensions than that shown at 19 in FIG. 1 and a radially extending portion 40 of that block passes through a short axial passage 41 lthrough the wall of the shaft 12'. In this case, however, the actuating mechanism is manually operated, as distinct from the pneumatic operation of FIGS. 1 to 3.

Each end of the shaft 12' is extended outwardly on the same axis, the right-hand extension being shown in FIG. 4 at 42, A second, rotary, shaft is located within the hollow shaft 12 and extends from end to end. This shaft has two threaded portions of opposite hands, one of which is shown at 43 and each of which is located within one of the portions of shaft 12 having the slots 41. A nut 44 threaded to the shaft portion 43 is secured to the inwardly projecting portion 40 of the block 19', so that, as the inner shaft 43 is rotated, the block 19' is moved axially. Also, because of the opposite hands of the threads on the threaded portions 43, the two blocks 19 of each slot 14 move in opposite directions, i.e. either towards or away from one another.

The inner shaft shown in FIG. 4 is constituted by a number of elements attached to each other end to end. Thus, the shaft has at each end of the shaft 42 a headed member 45 carried in a sleeve 46 within the end of the extension 42. This headed member 42 is bolted in the end of a tubular connection member 47 extending to the screw threaded portion 43 at the right-hand end of the shaft 12', as viewed in FIG. 4, that threaded portion being secured within the inner end of the extension member 47. A further extension member 48 is bolted round the inner end of the threaded portion 43 and connects to the threaded portion for the other set of blocks 19, at the left-hand end of the shaft 12. There then follows an extension member, similar to 47, and a headed member, similar to 45, the latter being arranged in the left-hand extension end of the shaft 12.

As will be appreciated, turning of either of the headed members 45, which for that purpose are designed to be gripped by a spanner, the threaded portions 43 are turned to cause inward or outward movement of the sets of blocks 19, and thereby to put the chains 17 into compression, or to release that compression. The locking mechanism operates as has already been described in relation to FIGS. 1 to 3.

lnstead of reducing the heads 21 of selected links, those links of the chain intended to move out of the slot 14 or 14 and to grip the reel may be of a size or form different from that of the other links, being so chosen that the pin heads are not retained in the rebates 15.

While reference has been made to the selected pins engaging the interior of a reel, it will be appreciated that the reel may be mounted on a tubular reel carrier which is located on the reel holder and with which the pins engage.

I claim:

1. A reel holder comprising a shaft having at least one externally opening, lengthwise extending slot formed with a transverse rebate, a length of chain adapted to be received in the slot with some only of the pins of the links of the chain retained by the rebate against radial movement with respect to the shaft, the remaining pins being free to move radially, and means for applying to the chain a lengthwise compressive force tending to force the nonretained pins out of the slot and into engagement with a member carried by the shaft.

2. A reel holder comprising a shaft having a plurality of externally opening, lengthwise extending, cruciform-section slots, each being formed with a pair of transverse rebates, for each slot at length of chain adapted to be received within the slot and having the pins of some links retained by the rebates against radial movement with respect to the shaft and the pins of other links free to move radially. and means for applying to each chain a lengthwise compression force tending to force the nonretained pins out of the slots and into engagement with a member carried by the shaft.

3. A reel holder according to claim 1 in which the nonretained pins have reduced heads compared with those of the retained pins.

4. A reel holder according to claim 2 in which one end of each of the chains is operated by actuating means within the shaft for applying the com ressive force. 7

5. A reel hol er accor mg to claim 4 1n WhlCh the shaft is hollow and each of the slots adjacent a chain end extends through the shaft, and in which there is a member secured to each chain, which member extends into the interior of the shaft and is operatively coupled to the actuating means.

6. A reel holder according to claim 5 in which the actuating means acts between the members at opposite ends of the chains to urge them axially towards one another.

7. A reel holder according to claim 4 in which the actuating means are fluid operated.

8. A reel holder according to claim 6 in which the members at one end of the chains are secured to a first piston slidably arranged within the shaft, while the members at the other ends of the chains are secured to a similarly arranged second piston, and in which there are means for applying fluid under pressure to the two pistons to urge them towards one another.

9. A reel holder according to claim 8 in which the ends of the shaft are closed, there are means for supplying fluid under pressure to one end of the shaft and there is a flexible fluid connection through the two pistons, putting the two shaft ends into communication.

10. A reel holder according to claim 4 in which the actuating means are mechanically operated.

ll, A reel holder according to claim 6 in which the members at one end of the chains are secured to a first nut within the shaft and the members at the other end of the chains are secured to a second similar nut, the two nuts being threaded on threaded screws or screw portions axially disposed within the shaft.

12. A reel holder according to claim 11 in which the screws are secured together for common rotation within the shaft. 

